tmakin/ack-tegra
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

bpftool: Fix undefined behavior caused by shifting into the sign bit

Browse Source 
Replace shifts of '1' with '1U' in bitwise operations within
__show_dev_tc_bpf() to prevent undefined behavior caused by shifting
into the sign bit of a signed integer. By using '1U', the operations
are explicitly performed on unsigned integers, avoiding potential
integer overflow or sign-related issues.

Signed-off-by: Kuan-Wei Chiu <visitorckw@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Quentin Monnet <qmo@kernel.org>
Link: https://lore.kernel.org/bpf/20240908140009.3149781-1-visitorckw@gmail.com
This commit is contained in:
Kuan-Wei Chiu
2024-09-08 22:00:09 +08:00
committed by Andrii Nakryiko
parent 12707b9159
commit 4cdc0e4ce5
1 changed files with 4 additions and 4 deletions
Download Patch File Download Diff File Expand all files Collapse all files
tools/bpf/bpftool/net.c
+4 -4
View File
@@ -486,9 +486,9 @@ static void __show_dev_tc_bpf(const struct ip_devname_ifindex *dev,
if (prog_flags[i] || json_output) { if (prog_flags[i] || json_output) {
NET_START_ARRAY("prog_flags", "%s "); NET_START_ARRAY("prog_flags", "%s ");
for (j = 0; prog_flags[i] && j < 32; j++) { for (j = 0; prog_flags[i] && j < 32; j++) {
if (!(prog_flags[i] & (1 << j))) if (!(prog_flags[i] & (1U << j)))
continue; continue;
NET_DUMP_UINT_ONLY(1 << j); NET_DUMP_UINT_ONLY(1U << j);
} }
NET_END_ARRAY(""); NET_END_ARRAY("");
} }
@@ -497,9 +497,9 @@ static void __show_dev_tc_bpf(const struct ip_devname_ifindex *dev,
if (link_flags[i] || json_output) { if (link_flags[i] || json_output) {
NET_START_ARRAY("link_flags", "%s "); NET_START_ARRAY("link_flags", "%s ");
for (j = 0; link_flags[i] && j < 32; j++) { for (j = 0; link_flags[i] && j < 32; j++) {
if (!(link_flags[i] & (1 << j))) if (!(link_flags[i] & (1U << j)))
continue; continue;
NET_DUMP_UINT_ONLY(1 << j); NET_DUMP_UINT_ONLY(1U << j);
} }
NET_END_ARRAY(""); NET_END_ARRAY("");
} }